gfs2: Use wait_event_freezable_timeout() for freezable kthread

A freezable kernel thread can enter frozen state during freezing by
either calling try_to_freeze() or using wait_event_freezable() and its
variants. So for the following snippet of code in a kernel thread loop:
  try_to_freeze();
  wait_event_interruptible_timeout();

We can change it to a simple wait_event_freezable_timeout() and then
eliminate a function call.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/log.c

@@ -1337,9 +1337,7 @@ int gfs2_logd(void *data)
 
 		t = gfs2_tune_get(sdp, gt_logd_secs) * HZ;
 
-		try_to_freeze();
-
-		t = wait_event_interruptible_timeout(sdp->sd_logd_waitq,
+		t = wait_event_freezable_timeout(sdp->sd_logd_waitq,
 				test_bit(SDF_FORCE_AIL_FLUSH, &sdp->sd_flags) ||
 				gfs2_ail_flush_reqd(sdp) ||
 				gfs2_jrnl_flush_reqd(sdp) ||

fs/gfs2/quota.c

@@ -1603,11 +1603,9 @@ int gfs2_quotad(void *data)
 		quotad_check_timeo(sdp, "sync", gfs2_quota_sync, t,
 				   &quotad_timeo, &tune->gt_quota_quantum);
 
-		try_to_freeze();
-
 		t = min(quotad_timeo, statfs_timeo);
 
-		t = wait_event_interruptible_timeout(sdp->sd_quota_wait,
+		t = wait_event_freezable_timeout(sdp->sd_quota_wait,
 				sdp->sd_statfs_force_sync ||
 				gfs2_withdrawing_or_withdrawn(sdp) ||
 				kthread_should_stop(),